Portable metal-turning lathe



G. W. PRISBREY.

PORTABLE METAL TURNING LATHE.

APPLICATION FILED DEC. 11. 1919.

1,352,380 PatentedSept. 7, 1920.

2 SHEETS-SHEET I.

UNITED. stares ear GEORGE W. PRIsBEEY, 0E s11. GEoRsE, UTAH, ASSIGNOR-OF ONE-SIXTH TO BRIGHAM CARPENTER AND ONE-SIXTHTQ ROBERTIFAWCETT, on ST. GEORGE. UrAH.

PORTABLE METAETUEEIEGEATHE.

Specification of Letters Patent. Patent- 5d Sept; 7, 192g};

Application filed December 11, 1919. Serial No. 344,013.

To all whom it may concern: I

Be it known that I, GEORGE W. PRISBREY,

a citizen of the United States, residing at new and useful Improvements inPortable Metal-Turning Lathes and I do declare the following to be a full, clear, and exact de scription of the invention, such as will e11 able others skilled in the art to which it appertains' to make and use the same.

My invention relates to improvements in portable lathes and more particularly to one or novel i'oim well adapted ior use by gunsiniths in reducing metal rods for numers ous purposes, such asi'orming screws there-- from.

v The principal object of the invention is to provide a simple, inexpensive and easily operable lathe which may be used either by holding it in a vise and turning the work with a pipe wrench or the like, or by holding the work stationary and turning the lathe, the arrangement being such as'to permit the turning of rods having different diameters and lengths. 4 l

Another object is to provide a lathe of the type set forth having feed means of novel form for properly advancing the cutter to the work, means being provided however for throwing said feed means out of play when the tool is to be used for cutting off the work' or for finishing an end or shoulder.

.1 Still further objects are the provision of simple and effective means for'clamping and centering the work and for holding it in proper relation with the cutter.

With the foregoing inf view, the invention resides in thernovel construction and arrangement of parts hereinafterr described and claimed, the descriptive matter'being supplemented by the. accompanying drawings. I

-Figural is an end view of a lathe constructed in accordance with my invention. 3 Fig. 2 is a transversesection onthe plane of line 22 of Fig. f

. Fig. 8 is a longitudinal section as inclicated by line 3-3 of Fig.1. V

Fig; 4 is a side View. q

Fig. 5 is a horizontal section on the plane of line 55 of Fig. 2. i

Fig.6 is a perspective view of the cutter parrying slide.

, F ig. 7 is a perspective view ofa bushing used when turning rectangular work. 7 v In the drawlngs above briefly described,

Ear @EE'ECE.

the numeral 1 designates a preferably rec tangular head'iorrned, of a single metal v blockprovidecl with acentral work receiving opening 2. Two opposed corners oft-he head are preferably provided with threaded sockets 3 by means of which. apair of handles (not shown) maybe attachedfor the purpose of turning the head upon the work when this is advisable. At one side of the opening 2, the head 1 is provided with a longitudinal groove or guide-way 4 having undercut sides,and a dove-tail base 5 on a i 4' slide 6, is received in said grooveor guideway. The slide 6 carries a cutter 7 extending into the opening 2,and by means of a suitable screw 8-, said slide maybe adjusted for turning the work to different diameters. The cutter 7 by preference projects adjust- .ably through a transverse opening 9 in the slide 6 and is provided on its outer end, with a crosshead 10' through which threaded studs '11 pass slidably. These studs: project rigidly from the slide 6 and are provided with nuts 12 bearing'against the'crosshead 10, and by 'adjus'tingth'ese nuts,- thecutter maybe set inthe most advantageous manner, Another guide-wayl3 is formed in the i 7 head "1. and. preferably extends parallel with the guide-wayt, said guideway 1,3 receiving a slide 1 1-. whose: inner endis shaped to form a shoe l5for' contact with the work to counteract the'thrustoi the cutter 7. Any appropriatescrew or'the like 16 may be pro- ,vided for adjusting the slide ltaccording to the diameter of the work, and although I have. shownthis slide positioned at right angles to the cutter'7,it might well bealined with said cutter... Similarly, although I have shownand described anumber of preferred details of construction with reference to the head 1, the cutter 7 and t'headjusting means for said cutter, other features of construction'ini'ght be used in'somejinstances. I c

Inconnect'ion with the i eatures above describedor their equivalents, I prefer to employ novel feedmeansior the work which consists. briefly off'a'feed nut 17 carried by the head 1, a sleeve l8 threaded through said nut adapted to receive the work. 19, and means for centering and clamping the work in sa'id sleeve. Bythis arrangement,when

the work 19 and the head 1 are relatively turned, the cutter 7 is properly advanced 1 along the workto remove a shaving of 7 ing the nut 17 and sleeve 18'against relative for movement bodily with the head, but for thickness'equal to the pitch of the screw threads'2O by means of which the nut and sleeve are connected. At times, for instance when finishing an end of the work or a shoulder, the feed should be discontinued and the head merely allowed to turnaround the work, or vice versa, and in order that this may be done, I provide means for holdturning, but allow the head and nut to turn with respect to each other. To attain this end, the nut 17 is swiveled on the head 1 and means is provided to normally lock said nut releasing said nut when desired.

An annular internally channeled bearing 21 is preferably provided to surround the nut 17 and receive the relatively narrow peripheral edge 22 thereof, and by means of suitable spacers 23,the bearing 21 is rigidly carried by the head 1 in such position as to alinethe sleeve '18 with the opening 2. A set screw 24E is shown threaded through the bearing 21 and receivable in-an'opening 25 in the nut 17 for normally holding the latter against turning with respect to said hearing, but when thls screw is released, free relative movement of said nut and bearing is permitted. a

To hold the nut 17 and the sleeve 18 against relative turning when said nut is released to turn in its bearing 21, Iflprefer that said sleeve 18 be provided with a stop 26 to abut said nut, and this stop isin most instances in the formot an external circumferential rib on the sleeve. ,lVhen the stop and nut are in contact with each otherand screw 2a is released to allow turning of the feed the cutter to the work;

The means for centering and clamping the work inthe sleeve 18 may well'vary, but is preferably constructed as follows: Opposed lateral arms 26 are formed on the sleeve 18 and are provided withlongitudinal guideways27 in which sliding jaws 28 are mounted. Theouter ends of the arms 26 are provided with sockets 29Iinwhich heads 30 are swiveled, said heads having bores 31 in which stems 32 are threaded, said stems being carried by the jaws 28. The jaws in question may'well be held in their guideways 27' by. adetachable plate 33 and this plate may wellcarry lugs Mi -received in grooves in the heads 30, said lugs and grooves serving to prevent removalot said heads from the sockets 29.

In describing the operation, although the work can be held and the lathe rotated, we willassume-that'the head 1 is clamped in a vise and that a pipe wrench or other suitable tool is employed for rotating the work 19. and is centered and clamped therein by the jaws 28 which are operated byturning of the heads 80; Ifthe workis to be turned down or it threads areto be'chased thereon, the feed nut 17 is'held with respect to the head 1, with the result that'turni'ng of the work threads the sleeve 18 through saidnut and thusproperly advances the work to the cutter, adjustment of the latter having been previously effected. If the tool is to operate on a portion of the-work. greater in length than the threaded part of the sleeve 18, this This work is inserted in the sleeve 18' sleeve may be unscrewed from the nut after performing part of the Work and then advanced along the latter by loosening the j aws'28. When these aws are again tight ened, the tool may be operated for furth'er cutting. r

Whenever the feed is to be discontinued, thescrew 2-1 is released and by then threading the'sleeve 18 into the nut 17 until the stop 26- abuts said nut, the work, its carry:

ing sleeve 18, and the nut in question'may rotate as one unit and thus the tool and work willnot be relatively shifted. 1 i

When turning square stock,'the bushing illustrated in Fig. 7 may be'insertedin the opening 2, said. bushing being provided'with a cylindrical outer surface 35 for contact with the shoe la'andwith a rectangular opening 36 to receive theworkQ The .devlce; iscomparatively simple and inexpensive, may be used to great advantage for numerouspurposes, and is desirable in every way, and since probably. the best results maybe obtained from'the details dislosed, they may well be followed it desired. 'I wish it understood however that within the scope of theinventionas claimed, numerous minor changes'may well be made. I claim; 1. In a'metal tur'ningflathe ahead having cutter carried 'by said head. adjacent said opening, spacers exte'njdingrigidly' from said head aroundthe openingthereof, an annular internally channeled bearing carried rigidly by said spacers in spaced relation to said head, a substantially flat feed nut rotatably mounted inthe channel of. said bearing in alinement with saidopening, a set screw carried by said bearing for holdtherethrough a work-rece ving openlng, a

tending into said opening, a feed nut carried by said head, a sleeve threaded through said nut, outstanding arms on said sleeve having 15 longitudinal guide-Ways, said arms having sockets, Work centering and clampingjaws slidable in said guide-Ways and having threaded stems, and heads swiveled in said socketsand having bores in which said stems 2o are threaded.

In testimony whereof I have hereunto set in hand.

GEORGE W. PRISBREY. 

